1. Field of the Invention
The present invention relates to a belt-type bucket elevator in which each bucket is fastened to the belt by means of movable fastenings arranged one behind the other in conveying direction.
2. Description of the Prior Art
German Offenlegungsschrift No. 2,732,932 describes and shows belt-type bucket elevators of the type described above which are particularly suitable for coarse-grained materials to be conveyed. As described in German Offenlegungsschrift No. 2,732,932, it is known to fasten buckets to belts by means of a fastening or fixing strip with screws or by means of a flat steel strip vulcanized into the belt. In addition to the pendulous support of the buckets on the belt, these types of fastenings have the disadvantage that material may get jammed between the belt and the back of the bucket and, consequently, the belt may become damaged. Fastening the buckets by means of a flat steel strip vulcanized into the belt is very expensive. When the buckets are fastened to the belt by means of eyelets vulcanized onto the belt, the belt is suitable only for excavating operations requiring small forces because the adhering force of the eyelets to the belt is small. The German Offenlegungsschrift No. 2,737,932 has as its object to provide a bucket elevator which is suitable also for coarse material to be conveyed and for high conveying capacities. In particular, the fastening of the bucket to the belt is to be able to absorb high excavation forces, is to ensure a quiet operation of the belt and a long service life.
In accordance with German Offenlegungsschrift No. 2,732,932, in the belt-type bucket elevator, each bucket is fastened to the belt by means of at least four fastening strips arranged into rows. The rear wall of the bucket is mounted by means of fastening angle pieces screwed onto the rear wall, so that the rear wall of the bucket is maintained a distance away from the belt and jamming of material to be conveyed is avoided. This known manner of fastening the buckets to the belt by means of two rows of fastening strips is intended to prevent a pendulous motion of the buckets. The distance between the belt and the rear walls of the buckets can be selected in accordance with the grain size of the material to be conveyed. In addition, the distance between the belt and the rear walls of the buckets can be adjusted subsequently as desired.
German Pat. No. 932,118 describes and shows a bucket elevator for granular material, such as barley, green malt or the like. The buckets of the excavator are fastened to two link chains. In the discussion of the prior art, German Pat. No. 932,118 mentions that bucket elevators are known in which deflecting walls are mounted in the front of the openings of the bucket, so that these excavators can be used for vertically as well as horizontally transporting the material to be conveyed. However, the buckets are formed in one piece. The known excavators have the disadvantage that the buckets do not by themselves take up the material to be conveyed; rather, the material must be conveyed into the buckets by means of a chute. Particularly at the location where the buckets travel around a guide roller, the buckets only incompletely receive the material to be conveyed. It is the object of the German Pat. No. 932,118 to provide a bucket excavator for granular material and particularly a bucket elevator to be used for traveling heap malting, in which the danger of falling and crushed grains in the bucket operation are essentially avoided. This object is to be met in that each bucket includes a main bucket portion and a front bucket portion connected in an articulated manner to the main bucket portion. The front bucket portion is mounted in front of the opening of the two-piece buckets seen in conveying direction and forms a deflecting wall. This deflecting wall catches and prevents from falling those particles of the granular material which could be thrown out of the buckets due to acceleration at the locations where the belt is guided from one conveying direction into a subsequent different conveying direction.
It is, therefore, the primary object of the present invention to provide a belt-type bucket elevator in which particularly small guide rollers can be used, which can be operated with relatively high conveying speeds and in which the danger of the formation of wedge-shaped spaces between the belt and each bucket during travel of the bucket around the guide roller is avoided as much as possible, so that additionally the danger is reduced that such wedge-shaped spaces be filled with material which would impair the operation of the belt. Specifically, these wedge-shaped spaces would prevent the bucket from returning into the normal position when the belt travels along a straight line. In addition, it should be possible to use simple fastening means for the buckets. By improving the manner of operation of the belt, the speed of travel of the belt can also be improved.